Why are intrinsically luminous, hot O and B type stars frequently observed despite being extremely rare?

Answer

Their tremendous output allows them to be spotted across vast interstellar distances.

Hot stars are intrinsically very luminous. Their brightness overcomes interstellar dust and distance, making them disproportionately visible in our night sky view even though they are few in number.

Why are intrinsically luminous, hot O and B type stars frequently observed despite being extremely rare?
astronomytemperaturestarsstellar evolutioncommonality